Contrasting genetic diversity in the genus Acanthodactylus (Squamata: Lacertidae) at its eastern distribution edge

This study examines the phylogeny and genetic diversity of the genus Acanthodactylus in the easternmost part of its distribution range, particularly in Pakistan. Using a concatenated dataset of mitochondrial (16S, COI, cyt b) and nuclear (Rag1) genes, we reconstructed the phylogenetic relationships using two tree-building methods that consistently revealed four strongly supported major clades (A–D). These clades exhibit significant genetic differentiation, with pronounced uncorrected p distances among them. Clade A, consisting of a single sequence identified as A. micropholis, is sister to the remaining clades. Clades B and C, both identified as A. blanfordii from the Helmand Basin in northwestern Balochistan, are geographically separated by the Chagai Hills and show moderate genetic differentiation. Clade D, identified as A. cantoris, is the most divergent and widespread clade, yet it shows shallow intraspecific genetic variation. An additional analysis of 177 cyt b sequences, including previously published data, supported our four main clades from the concatenated dataset. Clades B and C are novel and have not been identified before. Our research enhances the understanding of the evolutionary relationships and geographic distribution of Acanthodactylus in the eastern part of their wide distribution range and provides a well-supported phylogenetic framework for further taxonomic studies and conservation measures. Furthermore, we identify the type locality (“Ramnuggar”) of A. cantoris with Rasool Nagar (formerly called Ramnagar; 32.33°N, 73.78°E), Wazirabad District, Punjab Province, Pakistan.